After a short 15 minutes with the wind in your hair, you arrive at the viewing (and in my case, swimming) platform.
The tuna pen itself is 45m across, slightly larger than the hundreds of farmed tuna pens nearby. It is home to around 50 tuna, most of which are around 60 to 75kg.
We were assured by our guide that it's all perfectly safe, and highly unlikely that one of the great beasts would even graze us, let alone come smashing into me at their full speed of 60kp/h. Nerves aside, we donned wetsuits, booties, gloves and snorkels. All my cards were on the table and with a short leap, I was quickly submerged in ice-cold water before I had the chance to change my mind.
Squeals likened to those of lassoed pigs were possibly heard as far away as Tasmania, as the group thrashed around in the water, both terrified and exhilarated by the circling beasts below.
Tourists prepare for a day of swimming with tuna. Photo / Sarah Ivey
Once I'd regained my composure and got used to having my head under the surface to view the tuna up close, it was time for feeding.
"Just hold still and I'll throw you a pilchard to feed them."
Right, I must stay calm, I thought. It's only a tiny fish and I'm sure to catch it. Poised, he threw. I dropped it. Before I knew what had happened, a large tuna, which had clearly anticipated my incompetence, swooped in and snatched the fish from in front of my nose. I screamed with fright and, although of course I was unharmed, that was "hand feeding" days over for me.
As much as I don't care to tell you, I have to admit that others in the group were very successful, and had no trouble either catching the fish (which is much harder than it sounds) and subsequently feeding it to the tuna. I watched from afar and used the excuse that it was far more important for me to be taking photographs. Which, of course, it was.
From a more comfortable distance, I was able to take note of the sheer beauty of these calm, calculated animals. With a mere shake of their tail fin, they're propelled forward at lightning speeds, their blue bodies gleaming with every hint of sunlight.
The Tuna farm at Port Lincoln, South Australia. Photo / Sarah Ivey
They all seem to have their own agenda, yet they never seem to get in one another's way. It's as though they're circling the Arc de Triomphe roundabout with better insurance policies.
After about 45 minutes in the water we were pulled reluctantly from the enclosure and herded toward a smaller pool of colourful, far more docile fish. Bright blue, orange, a stunning display of aquatic life. The area is great for kids or slightly more timid guests if they're not quite game enough to hit the tuna pen.
A quick freshwater shower, a hot dog and a cup of hot coffee soon warmed us back up and it wasn't long before we bade farewell to the rolling sea and headed back to the mainland.
Now, some people thrive on the quintessential tourist experience, though others prefer to keep things au naturel.
Just up the coast from Port Lincoln is a population of Australian sea lions. Nestled in the sanctuary of Baird Bay, these rare seals run wild in their 3800ha, protected natural habitat.
A small tinny took us out to the colony, where big daddies were basking on the clifftops and mums and pups could be seen huddled together on the shore, keeping warm on the chilly, misty morning.
With the water at just 13C, it was definitely time to put the wetsuits back on. After dropping anchor, Alan our guide whistled to the pups. One by one they dragged themselves off the beach, the thought of play-time far too tempting for them to pass up
A few rings and balls were thrown into the water and soon the pups were in full swing. They tugged on ropes, pushed the balls around with their noses and begged for us to get in the water to play with them.
I was stunned by the similarities between the sea lion pups and any other young animals. Gentle and playful, they're simply a joy to watch.
We swam with them, played hide and seek, and got the odd nibble on the toe when the pups were a little too cheeky.
Swimming with the tuna. Photo / Sarah Ivey
Darcy, a young pup Alan has built a bond with, was crying to Alan, coercing him into the water. So he did. He stripped off to his Speedos and hit the tide. He tried telling me he was used to the water temperature and didn't need a wetsuit. I still maintain that he's a little bit mad.
The pair were like a synchronised ballet scene. Darcy mimicked Alan's every move, clearly revelling in the company and attention. From leaps to tumble turns, the pair were quite a sight to behold.
After 20 minutes in the water I was cold to the bone and had to get out. I watched for a while longer as other, slightly more thick-skinned swimmers played with the pups. Before long it was time to pull up the anchor and head off.
I had, until this point, been slightly cynical of the encounter. I had thought that the interaction from the pups may have just been because of their inquisitive nature.
However, as Alan started the engine and pulled up anchor, the pups began a loud chorus of cries. They tugged on the anchor rope and literally howled. They were genuinely sad to see us leaving and my heart jerked just a little bit. The babies were being left behind.
Curious fish pose for their close-up. Photo / Sarah Ivey
En route back to the base we went out across the bar, the entrance to the big, bad ocean. I'd heard stories of sharks and, to be honest, I've always been slightly scared of the ocean. So I had my eyes peeled for the great dorsal fin, expecting one to appear any moment.
Imagine my horror when not one, but seven, appeared in front of me. No, not sharks, but the fins of a family of offshore bottlenose dolphins. Alan basically threw us in the water. I was terrified. Here I was, out on the bar with a pod of huge dolphins "somewhere" around me. From the surface I couldn't see them. I lost my orientation and all I could hear was Alan shouting at me, "Put your head under, don't panic."
So I did, just as the pod swam beneath me. They must've been having quite the conversation. Possibly not about the neon pink colour of my toenails, but more probably along the lines of what kind of fish I was.
Alan mentioned that it was quite likely the pod had never had human interaction before. The echo location noises were absolutely phenomenal, like nothing I've heard before. Everyone's seen Free Willy but this was something else. Their curious nature had them stick around for a while with us, before they cruised off on their way.
Back on board, the adrenalin was fair humming through me. I felt like I had just touched a part of the world never touched before. I had done something real, something that pushed the boundaries. I had become a part of the wild.
CHECKLIST
Getting there: Air New Zealand flies non-stop from Auckland to Adelaide four to seven days a week.
In the water: See swimwiththetuna.com.au and bairdbay.com to organise your ocean adventures.
Further information: Create your perfect South Australia holiday at southaustralia.co.nz and australia.com.
Sarah Ivey was a guest of Tourism Australia.
